An example of a dummy block as secured to a stem is disclosed in U.S. Pat. No. 3,385,091. Such dummy blocks are commonly used to protect the stem portion and allow the dummy block to be made of material different from that of the stem. As shown in U.S. Pat. No. 3,385,091, the dummy block is secured to the stem by way of threaded engagement. Another form of threaded engagement of the dummy block to the stem is demonstrated in Canadian patent 1,190,518. Such threaded coupling of the dummy block to the stem of the extrusion press can create several problems during use. One of the most difficult problems in the assembly of the dummy block to the stem is that the dummy block may be at temperatures in excess of 800.degree. F. thereby necessitating care and the use of tools to effect the threading of the dummy block onto the stem. Occasionally, improper threading of the dummy block on the stem can result in cross-threading and hence, require re-threading of either or both of the dummy block and stem. Furthermore, improper threading can result in misalignment of the dummy block within the cylinder of the extrusion press container. This can require shutdown and reassembly or if the dummy block enters the container and is cycled through an extrusion cycle, the improperly threaded dummy block can strip the threads of the stem and virtually be welded thereto. This necessitates opening of the container and the use of a cutting torch to remove the dummy block from the stem.
It is also generally understood that over prolonged use of any threaded arrangement the threads can wear necessitating re-threading of either the stem and/or dummy block. It is also necessary in the assembly of the dummy block to the stem that the dummy block be positioned at a predetermined distance from the stem. This is particularly important in instances where it is desired that the dummy block float relative to the stem by virtue of the dummy block being able to move longitudinally of the stem as well as laterally thereof. It is not always possible during quick assembly of the dummy block to the stem to ensure that the correct spacing between the two components is provided.